Fixing a broken floor joist - Fine Homebuilding Tip
  • Read FHB on Your iPad
    Read FHB on Your iPad
  • Clever daily tip in your inbox
    Clever daily tip in your inbox
  • 7 Small Bathroom Layouts
    7 Small Bathroom Layouts
  • Inside a Model Remodel
    Inside a Model Remodel
  • Install a Vinyl Privacy Fence
    Install a Vinyl Privacy Fence
  • All about Roofing
    All about Roofing
  • Video Series: Tile a Bathroom
    Video Series: Tile a Bathroom
  • Design Inspiration
    Design Inspiration
  • 9 Concrete Countertop Ideas
    9 Concrete Countertop Ideas
  • Magazine Departments
    Magazine Departments
  • Deck Design & Construction
    Deck Design & Construction
  • 7 Trim Carpentry Secrets
    7 Trim Carpentry Secrets
  • Remodeling Articles
    Remodeling Articles
  • Energy-Smart Details
    Energy-Smart Details
  • Ultimate Deck Build 2015
    Ultimate Deck Build 2015
  • Basement Remodeling Tips
    Basement Remodeling Tips
  • Master Carpenter Videos
    Master Carpenter Videos
  • 7 Smart Kitchen Solutions
    7 Smart Kitchen Solutions
  • Tips & Techniques for Painting
    Tips & Techniques for Painting
Pin It

Fixing a broken floor joist

When our 1920s farmhouse was moved in the ’70s, it gained a new foundation and a couple of broken floor joists. The joists never were repaired, so by the time we bought the house, the floor had some distinctly springy spots. Working from below in a full basement, it seemed an easy proposition to sister a new joist to the side of a broken one. But my first attempts at bringing the joists together with C-clamps didn’t work very well. I couldn’t exert enough pressure to the top of the new joist to bring it flat against the old one.

As shown in the drawing, I ended up using the lightweight jack from my wife’s compact car to get the job done. It allowed me to work my way along the length of the joist, pressing it into place and nailing it to the broken joist. To keep the joists aligned on each side of the work, I used a pipe clamp to counter the force of the jack.

Click to enlarge image

Next Article
Next Article: Tip: